Honestly the tune is for the rest of the stuff I have on the car, like the cam and stuff.
Need help with fuel injectors
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Yeah I’m not even a fan of chips in general, but it’s mainly for my cam and also adjusting my computer because I did a T5 swap so I have the AOD computer which has the AOD shift points and stuff.
If your car is tuned you don’t need a calibrated MAF meter for the 24s. Just have the tuner update your injector information in the tune.
This.
Right before you get your tune swap the 24s in. The car will run rich, but then you can have the tuner adjust for the injectors in the tune itself.
You don’t need the MAF
as far as I know that computer doesn't know or care when the auto trans shifts.
there are differences in pin placement at the 02s and the hanging rpms when using a auto computer with stick swapped stang.
By the way, what heads do you have?
nevermind I see they are gt40
BBK, LMR, and Summit all told me the stock MAF doesn’t meter enough air for what i’m giving it and that I would need to purchase one that can meter more. Im not saying you guys are wrong i’m just trying to figure out what’s right you know? I hear a lot of different things.
Idk I hear a lot of different things, I’m just trying to take in what guys at LMR, Summit and BBK tell me. I’m no professional by any means which is why i’m on a forum in the first place lol, but from what they’ve told me I needed that MAF calibrated for the 24’s.
They are right about that. I would have never thought you would be running the tiny stock MAF on a 347, it’s a restriction on a stock engine and one of the 1st things I upgrade. You’re going to gain some power out of the upgrade. Might as well get one for 24s since you need one anyway.
I still think 24s are a mistake in that engine. You’re going to eventually want to swap heads to a nice set of aluminum heads and matching intake to maximize the power that 347 can give you and will be at the edge of those 24s. The car will run perfectly fine with 30s especially since you have a tune and the proper info can be put into the tune. The 30s will give you room to grow.
As for the EEC it knows nothing about the transmission as fox body computers don’t control the transmission like newer cars do. The auto computer does have a different timing curve and different dashpots idle control strategy than the manual computer but that’s about it. The EEC wiring harness pin out is different vs the manual computer.
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They are right in the sense that the stock 55mm MAF is too small in diameter.
However I probably would have suggested a 94-95 70mm MAF instead, considering you are tuning the car. Many ways to skin a cat here so there is not just one answer.
AOD is also not computer controlled. The shift points are controlled by a cable physically attached to the throttle body (TV cable) that mechanically controls it. Be aware though that using an AOD comp with a 5-spd might result is hanging idle occasionally.
For comparison, look at the maf and injector specs for the lighting truck, that 351 used the same gt40 head, 24lb injectors and a 76mm maf (I believe), there may be some differences in cams but nothing radical,
Again I will say having a chip is not needed for a well planned combination,
Again I will say having a chip is not needed for a well planned combination,
I appreciate the earlier "band-Aid" comment, but is it just me, or will the computer think 19# injectors at 50 psi are the same as 24# injectors at 40 psi?
I had a lean code, my mechanic turned my regulator up to 50#, it went away. I always figured I could switch to 24# injectors (mostly to get the newer style) and just turn it back to 40 psi...
I had a lean code, my mechanic turned my regulator up to 50#, it went away. I always figured I could switch to 24# injectors (mostly to get the newer style) and just turn it back to 40 psi...
AOD vs. manual computers do have some, probably noticeable, differences. The way it controls the fuel is a little different because with a stick car you are on and off the gas much more often than AOD. Also the rev limiter is set at 6200 rpm vs 7000 rpm on a manual computer. The car will run just fine, but you may notice it not completely smooth under certain situations, like it may not understand why the engine is coasting in neutral at 30mph when you're coming to a stop and do weird things with the idle.
You could get a chip and have them just upload a stock A9L tune on there and update the injectors to 24lb or what ever else you want them to optimize.
View: https://www.youtube.com/watch?v=to3368UdBTU&t=285s
You could get a chip and have them just upload a stock A9L tune on there and update the injectors to 24lb or what ever else you want them to optimize.
View: https://www.youtube.com/watch?v=to3368UdBTU&t=285s
I'm not saying it is how it is supposed to work. But, I do not believe fuel pressure is an input to the computer, so, it is blind there. It has a nozzle (the injector) and it "knows" the size. But, you can lie to it. Tell it the injector is 19#/hr and install one that is 24#/hr. With 50 psi fuel pressure, it will leave the injector open some period of time with the 19# injector, seeking the correct reading on the Oxygen sensor. With a nozzle about 25% larger (24# vs 19#), and pressure about 25% less (40 psi vs 50 psi), I believe the time the injector pulses for a 24# injector and 40 psi will be about the same. At least I expect it will run. Then again, the computer can adjust some based on the Oxygen sensor reading.
Seriously, if that won't work (and I'm not saying it is the right thing to do) I'd love to understand why.
Bill, what you are saying is correct... increasing fuel pressure does in fact make a fuel injector act like a larger injector than what it is 'rated' for. In fact if you look up the specs for any injector, they don't just list the flow rating, but also provide the pressure at which that rating applies.
This is an old school trick, which was used with great success for a long time. There is some risk... specifically very short pulse widths in low rpm situations can cause erratic fueling. This is why today, we call it a band-aid...
If it is working for you, great!
You could install a WBO2, and confirm that the ecu is able to hit the target AFR's, or watch fuel trims if you have that capability?
This is an old school trick, which was used with great success for a long time. There is some risk... specifically very short pulse widths in low rpm situations can cause erratic fueling. This is why today, we call it a band-aid...
If it is working for you, great!
You could install a WBO2, and confirm that the ecu is able to hit the target AFR's, or watch fuel trims if you have that capability?
Okay, I've wondered about this, so, let me ask you about WBO2s. Do they install instead of your O2 sensor and provide the signal to the ECU, or install in addition to your O2 sensor, in which case, I guess another fitting needs to be welded into the exhaust? Also, the big mystery with my 95 GT has always been the missing O2 sensors. The Ford dealer, and everywhere I have checked lists upstream and downstream O2 sensors for a 1995 5.0 Mustang GT. I think that is an OBD2 thing that is on 1995 V6s and 1996 and later 4.6s. But I have 2 sensors, not 4. Anyone else have this?
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